Cutter head



A. N CLARKE CUTTER HEAD Filed June 21, 1928 Patented Nov. 4, 1930 UNlTEDf's'rATl-:s

ALEX A; CLARKE, or CHICAGO, ILLINOIS CUTTER HEAD' Application filed June 21,

The present invention relates to cutter heads, and more particularly to heads adapted for use in portable cutting tools.

The primary object of the invention is the provision of a novel and efficient construction of cutter head having associated therewith a quickly insertible and removable cutter of relatively narrow width, and, therefore, relatively inexpensive to produce, thus permitting the blade to be discarded and thrown away after the same has become dull, and to be replacedexpeditiously by a sharp blade as occasion for replacement may arise. The use of such bladesmaterially reduces the weight V of the cutter head and .decreases the cost of blade upkeep..` The invention also aims to provide a cutter head equipped with a cutter blade of the Character mentioned the mounting of the blade within the cutter head being such as to provide a firm seat for the blade, The latter thereby is held firmly in position m the cutter head, and is `rigidly presented to the work during the cutting operation. Furthermore, Vthe invention contemplates novel locking means for holding the cutter blade in the cutter head, wherebyto accomplish the aforesaid quick insertion and removal of the blade to and'frointhel head, the replacement of the .blades being easily effected without .the use of special tools or other equipment. f Y

In the construction of portable cutting tools there are two primeffactorsto be conv sidered, viz., the security with which the vweight of the driven parts. -Due to the relatively small power unit which must be employed in tools of this character to reduce the weight of the tool to a minimum, and the desirability of Ydriving'the cutter'heads at very high speed, which is particularly true of cutter heads `such as disclosed herein,ri t.is necessary that the moving parts be light 1n order that the Vpower of the driving unit may be utilized in performing work, and not lostv ,in developing and maintaining the momentum of heavy parts.Y Furthermore, due tothe very high speed at which these devices *are C' operated,`it is essential that the parts beduy heavy the head may be made of steel. parts of the tool are held together, andthe y 'iti is drilled. to provide tangential sockets 1:3,

`'less `diameter than their outer ends.

1928. Serial N0.' 287,311.

rable and securely held. The-cutter head hereinafter described may be constructed of relatively light 'material and at the same time provide aj'durable and secure structure.

Further objects and advantages of the in-..l

lvention will be apparent to those skilledin the art upon an understanding 'of a preferred embodiment of the invention as setforth in the Vfollowing specification and the annexed drawings It is Ito beunderstood, however,;f5.0

that this disclosure is for illustrative pur-v Aposes'only, and is notto be construedas unduly limiting'the scope of the protection deined by the appended claims.

In thedrawings*` l is aview in elevationV of a cutter head embodying the present invention.

Fig. .2 is a sectional View on the line 2--2, Fig. 1. f n Figi?) isv ail-fragmentary face elevation ofl'7fI one of the `cutter blades. j Having lreference now in det-ail to theV accompanying drawings, the numeral 11 designates the cutter head. This is generally cylindrical. It is free from sharp corners or edges and constitutes what is commonly known to the art as a safety head.

4 YThe cutter head 11 is mountedon a shaft 12 land is operated therebyffrom suitable driving connections.

The head 11 preferably is made of aluminumor some metallic alloy which is relatively light. instances where the machine `in which the cutter head is to be used is relatively si At equdistant points aroundthe head 11 the inner ends of which sockets areof slightly These sockets are arranged in series longitudinally of the head 11, as shown in Fig. 1. rlfhe re'- stricted inner ends of the socket 13 are screw- 'threaded `and receive screw-threaded .flanged vbushings U14' the flanges 15 of which seat against shoulders 16 formed at thejunction of the restricted inner ends and the enlarged outer ends of'thesockets'l. These bushings 111 are also provided withkerfs 17 for receiv- -inga screw-driver or similar tool for permitting rotation of the bushings when .they are 190 introduced to and removed from the sockets 13.

The bushings 14 preferably are formed of steel or other hard and durable metal. They occupy positions within the sockets 13 with their flanges 15 disposed a short distance below the outer surface ofthe headull'. Each of thetbushings 14, the bore of which isscrewthreaded, receives a standard machinev screw 18, the heads of these screws snugly Afitting the enlarged outer ends'dfthe sockets 13.

After the several bushings 14 havebeeu introduced to and properly fitted in their respective sockets, and before introduction of the screws 18 to the bushings, a'plurality of slots 19, one for each longitudinal series of the screws 18 tothe bushings, 'a plurality of slots 1-9, one for eachlongitudinal series of the sockets 13,V is milled lengthwise of the face ofthe head 11. These slots 19 intersect the sockets 13,'and are disposed in such relation to the. bushings 14 that the Vside walls of the slots19 and the flanges of said bushings 'form an obtuse angle. The milling operation is continued until the edges of the bushings which are immediately` contiguous to the slots 19` are 'milled away to form flat bearing surfaces`20 which extend across the'bottoms of the slots 19, as best shown in Eig, 2.

A relatively narrow cutter blade 21 is received by each' of the slots 19, the inner edges of said 'blades resting upon the 4hard fiat bearing surfaces 2O which are affordedby the milled portions of the flanges 15of the bushings. These surfaces 20, therefore, constitute seats for thecutter blades 21, so that the latter areproperly supported within vthe cutter head for rigid preseiitationto the work. Each of the cutterblades l21 is provided witha plurality of equidistantlytspaced: semi-circu- :lar notchesQQ, one Vof these notchfe'sopening into the enlarged outerendof eachof the 'sockets 13`when the cutter blades :21am-Seated in the slots19, and thereby 'being accessible from the socket with which it'co'inmunicates. ThenotchesQQ are cut intothe cutter-blades 2.1 suiiicientlydeep toprovidean inclined seat 23 'at each iiotcli. The inclination of these featseorresponds to the angular disposition of the innerfaces of the heads ofthe screws 18,I and each Aofthese` notches receives the adjacent inar'ginalportion of oneof the.V screw heads. This interfitting of theheads of the screws 18.' with theA notches of the cutterV blades 21 establishes a'lockingrelation between the screws andthe cutter blades, and .securely -holds the blades in their respective slots 19.

Obviously, when the screws 18 are "removed so as towithdraw the headsthereof fromthe notches 22 the cutter blades may be easily removed froni the slots 19.r

VAt iiiointsadjace'ntto the cutter blades 21, and intersecting the outer ends of thesockets 13,`the face'of'the head 11 is milled length- J wise thereof to provide apluralityof `tonriiia'tei'ially reduced. The use of the bushings "reiate'dto'the slots lin which the cutter blades ai'enniounted in the manner shown provides 'for these cutter blades a firm seat, and enables their. to be rigidly presented to the work in the 'rotation of the head. Moreover, the interlocking relation of the heads of the screws andthe cutter blades insures proper retention of the cutter blades in their respective slots, but facilitates reinoval'of the blades when they become dull, and their replacement by sharp blades when so required. The use of relatively narrow blades permits their manufacture at little expense, and when a b ladehas become dull it may be thrown away with little loss.

I claim:y A p 1. A Icutter head fof the class described having elongated slots lacross its peripheral 'face, cutter blades positioned in said slots, hollow screws secured in said head to constitute seats Ifor said cutter blades, and additionalscrews threaded in saidv hollow screws to detachably hold the cutter blades locked againstsaid seats.v

ZA' utter head yhaving',elongated slotsY extendingacrossr its peripheral face, hardened 'bearing seats Aprovid'e'd'at intervals in the bottoihsrof said slots, cutter blades arranged V`'Ln'ls'aid yslots andpos'itiiied 'on said seats, andineans secured to `said seats for retainingsaidzbladesin said slots. u y ,Y A cutter Vhead having :elongated slots across yits face, hardened bearing seats provided at intervals fin-the base of said `slots cutter lblades positioned in said slots, l

and screwsretainedby' said seats and having their head por-tions overlapping the base -portioliispf said blades to hold the latter on lsaid bearingl seats.

1i. A jcutter 'headfhaviiig elongated slots i cut inthe peripheral face thereof, bushings sec'urediii the head with the upper ends thereofforminga part'ofthe 'base of said slots, cutter blades'arianged in said slots, and

screwsthrea'ded into said` bushingsand hav- A`ingth'eirfh'eads iiiterfitting with the base portions of the k"cutter bladesto 'detaehably hold Vsaid' blades' in" saidy slots. Y

5.- A, cutter headl having elongated slots across peripheral Y face, i bushings secured -in'the head and projecting int-o said slots to constitute the bottom walls of the latter, cutter blades Vpositioned inv said slots and having ltheir innerends seated upon and supported by said bushings, said blades havsaidv slots to form the base thereof and provide supporting seats therein, cutter blades mounted in said slots and seated upon said bushings, and means secured to said bushings for detachably holding the cutter blades in said slots.

7. A cutter head provided with a plurality of tangential sockets, and Valso having elongated slotsV extending across its peripheral face and intersecting said sockets, bushings mounted in said sockets andextending into said slots to form the base thereof and provide supporting seats therein, cutter blades mounted in said slots and seated upon said bushings, and screws mounted in ,said busliings and having their heads in engagement with said cutter blades for detachably holding the cutter blades in said slots.

8. A cutter head provided with a plurality of tangential sockets, and also having elon gated slots extending across its peripheral face and intersecting said sockets, bushings mounted in said sockets land extending into said slots to fornithe base thereof and provide supporting seats therein, cutter blades mounted in said slotsand seated upon said bushings. said cutter blades having notches torinediih the sides thereof adjacent to said bushings, and screws mounted in said bush-V ings and having their heads interlitted with the 'notches lof ysaid blades for detachably holding the cutter blades in said slots,

9. Aicutter head providedV with a plurality of tangential sockets, and also having elongated slots extending across its peripheral face and intersecting` said sockets, flanged bushings mounted in said sockets the flanges of which extend intosaid slots to provide supporting seats at the base thereof, cutter blades mounted in said slots and seatedupon the flanges of said bushings, and screws mounted in said bushings and having their heads in engagement with said cutter blades for detacliablyholding the cutter blades in said slots.

10. A cutter head provided with a plurality of' tangential sockets, and also having elongated slots extending across its peripheral face and vintersecting said sockets, saidA slots being disposed in angular relation to said sockets, flanged bushings mounted inA said sockets and having their lianges ex# tending into said slots to provide supporting seats at the base thereof, the portions` ofthe flanges extending into said, slots being cut away, cutter blades mounted in said slotsand seated upon the cut-away portions of said flanges, and means cooperating with said bushings and said blades for detachably holding'the latter in said head.

l1. A cutter head provided with a plu rality of tangential sockets, and also having elongated slots extending across its peripheral face and intersecting -said sockets, said slots being disposed in angular relation toV said sockets, flanged bushings mounted in said sockets'and'having their flanges extending into said slots, the portions of the flanges extending into said slots being cut away to provide supporting seats at the bases of said slots, cutter blades mounted in said slots and seated upon the cut-away portions of said fianges, and screws threadably engaged with said bushings and having their heads in en-V gagement with the base portions of said blades for detachably `holding the latter in saidislots. i

12. A cutter head provided with a` plural ity of tangential sockets, and also having elongated slots extending across its peripheral face and intersecting said sockets, said slots being disposed in angularrelation to said sockets, flanged bushings mounted vin said sockets and having their lianges extending into said slots, the portions of the flanges extending into said slots being cut away to@ provide supporting seats Vat the bases of said slots, cutter blades mountedv in said slots bushings, and screws threadably engaged with said bushings and having their heads `interiitted with the notches of said blades for detachably holding the cutter blades in said slots. Y i

13. A cutterhead having a socket in its peripheral face arranged tangentially to the axis'of said head, and also having a slotl in said face extending across the lat-ter and intersecting said socket, a bushing seated in said socket andhaving a portion projectinnf into said slotto constitute the base thereot, a cutter blade seated in said slot and resting on said bushing to be supported by the latter, and meanssecured to said bushings for detacliably holding the cutter blade in said slot.

14. A cutter head having a socket in its peripheral face arranged tangentially to the axis of said head, and also having a slot in i into said slot to constitue the base thereof, a

cutter blade seated in said slot and resting on said bushing to be supported bythe lat- 1 tei', and a screw threadably engaged with; said bushing and having its head interiitted with the cutter blade for detachably holding the latter' in said: slot. l Y

15. A- cutter head having a socket in `its peripheral face arranged tanentially to the axis of'said head, and alsohaving a slot in said face extending across the latter and intersecting said socket, a flanged bushing seated in said socket and having a portion of its fiange projecting into said slot to constitute the base thereof, a cutter blade seated in said slot and resting on the flange of said bushing to be supported by said flange, said cutter blade having a notch formed in the side thereof adjacent to said bushing, and a screw threadably engaged With said bushing and having its head intel-fitted with the notch of said blade for detachably holding the cutter blade in said slot.

1G. In a device of the class described, a supporting member, pairs of screws adjustably threaded in said supporting member, one of the screws of each pair vbeing threaded into the other, and a cutter blade located and fiXedly held in place by the threaded engagement of said pairs of screws,one screw of a pair constituting'a seat foi` locating the associated cutter blade.

In testimony whereof I have hereunto subscribed my name.

ALEX A. CLARKE. 

